1. Field of the Invention
This invention pertains to a refrigerator of a type wherein a fan forces air to circulate within a chamber containing refrigerated contents, and wherein a switch is arranged to disable the fan when a door of the refrigerator is opened, particularly but not exclusively a freezer or other refrigerator as may be used to merchandise frozen foods, dairy products, and other products.
2. Description of Prior Art
It is conventional for a refrigerator of the type noted above to comprise a cabinet, means to refrigerate contents of a chamber within the cabinet, one or more doors for access to the chamber, and one or more fans to force air to circulate within the chamber so as to evaporate excess moisture within the chamber, and so as to eliminate stagnant regions within the chamber.
It is conventional for a switch to be mounted for operation with each door so as to switch to a first mode when such door is closed in normal operation, and so as to switch to a second mode when such door is opened in normal operation, and for the switch in its first mode to enable the fans to be energized and in its second mode to disable the fans.
It is conventional for several switches to be connected in series, so as to disable the fans whenever any one of the switches is in its first mode. Each switch may be a conventional switch having a plunger or similar means to switch the switch to its first mode whenever the plunger or similar means is depressed, as by closure of a door, and having a spring to bias the plunger oppositely so as to switch the switch to its second mode whenever the plunger or similar means is released.
It is desirable for the fans to be disabled when a door of the refrigerator is opened so as to minimize infiltration of ambient air. However, particularly but not exclusively in commercial freezers, dairy cases, and other refrigerators as may be used to merchandise frozen foods, dairy products, or other products, certain shortcomings have been ascertained in prior arrangements of one or more switches to disable one or more fans as discussed above.
Specifically, and particularly after many cycles as may be expected to occur in commercial freezers and other refrigerators used to merchandise various products, a switch mounted for operation with a door as discussed above may fail so as to remain in its second mode whether the door is opened or closed, whereupon the fans may remain disabled whether the door is opened or closed. Consequently, undue rise in interior temperature may result from inadequate circulation of air, and undue loads may be placed on a compressor and other components of the refrigerator.
Thus, there remains a need for improvement in a refigerator of the type noted above, particularly but not exclusively in commercial freezers, dairy cases, and other refrigerators as may be used to merchandise frozen foods, dairy products, and other products, wherein many cycles of such switches associated with such doors may be expected to occur.